This invention relates to optical fibre cables, particularly to such cables for submarine use.
British Pat. No. 1,550,588 (C. S. Parfree-P. Worthington) discloses an optical fibre cable which includes one or more optical fibres located within a tubular electrical conductor over which there is a cylindrical strain member. Optical fibre cables offer the advantage for submarine telecommunication systems, of propagating the signal over relatively long distances before the signal needs amplification in a repeater. It is estimated that the repeater spacing can be as much as 30 or even 50 km in optical fibre submarine communication systems in the near future.
The repeaters are powered electrically, the power being supplied from a terminal via the tubular metal conductor as disclosed in British Pat. No. 1,550,588.